Starting with the `v3` release, this action will delegate to `gradle/actions/setup-gradle`.
All repository sources have been migrated to https://github.com/gradle/actions, and
are no longer required in this repository.
Workflows testing the action functionality have been retained, but any workflows involving
building or inspecting code have also been migrated to `gradle/actions`.
The test Gradle sample apps reference plugins, and it's good to keep these
updated (particularly the GE plugin).
Minor changes to the build scripts were required to satisfy Dependabot.